Is there a way to make a listener for a key press to begin a loop?
Example: I press the Tab key on my keyboard and the programmed loop begins running.
Essentially creating a keyboard hotkey.
The answer is yes and no.
Only the Arduino and its IDE, no.
The way I found is to use Processing to wait until it detects a hotkey, then send a serial message to your Arduino. If you tune in the right COM port, this should work.